Many buildings have a foundation in the form of a crawl space or a basement. And in most cases the majority of the foundation is underground with a soil, gravel, or concrete floor. But unfortunately, the floor is also often lower than adjacent ground water. This can cause water to seep through the foundation and into the building. This water may encourage microorganisms to grow in the building and may also erode the foundation.
Some builders attempt to solve this problem by installing a moisture barrier, such as plastic, over the floor of the foundation. Although this barrier can reduce the building's exposure to minor amounts of water that is present below the barrier, it does nothing to remove water from a truly wet foundation. In fact, the barrier may actually hold water and prevent it from draining.
One way to solve this problem is to install drain tile in the floor. This approach requires a sump pit and a trench along the inner perimeter of the foundation to hold the tile. The trench and commonly the pit's perimeter are then both filled with aggregate. The drain tiles then collect water from the floor as it seeps through the foundation and guide it into the pit. The system may also include a pump to remove the water from the pit when it exceeds a predetermined level.
A similar system is shown in U.S. Pat. No. 3,562,982 to Parezo which is hereby incorporated into this specification by reference. Notably, this system does not remove all the water that is present in the crawl space, nor does it eliminate the need for a moisture barrier. Instead, this system simply removes excess water in the crawl space and keeps it under the barrier so that the remainder of the building is not exposed.
While this system is effective, it is also costly to install once the building has been built. For example, one costly aspect is the movement of the aggregate into the crawl space or basement and the laborious task of placing it in position. The gravel is first slid down shoots and then moved by hand to the desired location with a shovel or a sled.
Moreover, a less complex drain system without drain tiles or a trench might be used in some situations where the moisture problem is not so severe. But unfortunately, these alternatives also require additional aggregate. Hence, these alternative systems are not used because they are not cost-effective. The labor-intensive and generally expensive methods that are currently used to place the aggregate quickly offset any savings that the alternative methods may otherwise offer.
What is needed is a way to reduce the cost of installing drain-tile systems as well as a way to make any alternative system that uses aggregate more cost effective. And this invention addresses that need.